在 Net Core 中为 Streaming 类创建 Observable

Question

如何为类创建 Observable？ 例如，这里是持续销售类

public class Product
{
     public int ProductId {get;set;}
     public string ProductDescription {get;set;}
     public float Sales{get;set;}
}

如何创建 Observable？假设他们使用 Add() 进入 List<Product>，产品会不断添加代表交易。

任何时候，一个产品被添加到控制台程序的任何地方，订阅者都会观察到它。

var productSample1 = new Product { ProductId = 1, ProductDescription = "Furniture" };
var productSample2 = new Product { ProductId = 2, ProductDescription = "Book" };
var productSample3 = new Product { ProductId = 3, ProductDescription = "car" };

var productlist = new List<Product>();
productlist.Add(productSample1);
....
productlist.Add(productSample2);
...
productlist.Add(productSample3);

也许是这样的，

var products = Observable.FromEventPattern < EventHandler<Product>, Product>();

尝试阅读下面的资源，尝试添加，

Generate numbers at random time intervals with rx

Intro to Rx

Answer 1

您可以使用ObservableCollection:

var list = new ObservableCollection<int>();
using (var o = Observable
    .FromEventPattern<NotifyCollectionChangedEventHandler, NotifyCollectionChangedEventArgs>(h => list.CollectionChanged += h, h => list.CollectionChanged -= h)
    .Subscribe(e => Console.WriteLine($"{e.EventArgs.Action} {e.EventArgs.NewItems[0]}")))
{
    list.Add(1);
    list.Add(10);
}

// Add 1
// Add 10

或者转过来从订阅中添加：

var list = new List<int>();
var subject = new Subject<int>();
using (var o = subject.Subscribe(i => list.Add(i)))
{
    subject.OnNext(1);
    subject.OnNext(10);
}

foreach (var i in list)
{
    Console.WriteLine(i);
}

// 1
// 10